Selecting system.



A. F. DIXON. I SELECTING SYSTEM.

- AP.PL|CAHON FILED MAR. 19. I914.

Patehted Au". 29,1916.

[/5 vemorr Amos F, Dixon and exact description.

transmission type, although obviously not -co1i1panying drawing in which the circuit utilized for transmitting and receiving selecnnnrnn srnrns PATENT curios.

AMOS F. DIXON, OF NEWARK, NEW JERSEY, ASSIGNOR, BY IvIESNE ASSIGNMENTS, TO WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATION OF NEW YORK.

SELECTING SYSTEM.

PatentedAu 29, 1916. Application filed March 19, 1914. Serial No. 825,802.

Specification of Letters Patent.

erates a current control means by selectively transferring a characteristic combination of movable contacts, 1 to. 5 inclusive, from the negative-to the positive pole of a battery 6. The depression of the key likewise initiates 80 the operation of'a plurality of cut-ofi relays 11 to 15 inclusive, and connecting relays 21 to inclusive, whereby a series of impulses is transmitted to the line and the local apparatus, the character of the impulses being determined bythe location of the key contactsl to 5. A plurality of selecting relays 31 to 35 inclusive, forming a. part of a selecting mechanism, are arranged to be actuated only on. positive impulses, and these relays cause the energization of a plurality of corresponding selecting magnets 41 to 45 in elusive. These selecting magnets control the operation of mechanical selective apparatus whereby the desired character or operation is chosen. When used merely as a receiver, the line impulses efi'ect the successive operationof the cut-off relays 11 to 15 and the connecting relays 21 to 25,;the polarity thereof determining the actuation-0f the selecting relays 3 1 to 35, and consequently the selecting magnets nu) 45.

A betterunderstanding of the system can .be obtained from a. description of the selection of a specific character and the various operations, such as spacing, shifting, etc. both when acting as a combined printer and transmitter and merely asa receiving printer. Assume, for example, that the letter F is to be printed at the home-station 0 and impulses,transmitted to effect its being also printed at a distant station, and that the combination of impulses required is plus, negative, plus, plus, negative. The depression of the F key of the keyboard will transfer key contacts 1, 3 and 4: from nega tive to positive battery. It will also transfer a pair of movable contacts 50 and 51 from fixed'contacts 52 and 53 to'fixed contacts 5st and 55 respectively, and a further set of contacts 56' will be closed. Contacts 50 and 51 areadapted to be thus transferred and contacts 56 to be thus closed upon the actuation of every key on the keyboard for purposes which will appear as the description progresses, The closing of contacts 56 completes a circuit from grounded battery 60, I through a-jreyboard magnet 61, contacts 56, i conductor (32, back contact and armature of cut-oil relay 15, conductor 68, contacts 64 1 b all whom it may concern lie it known that I, Amos F, DIXON, a citizen of the United, States, residing at Newark, in the county of Essex and State of Xeu' Jersey, have invented a certain new and useful Improvement in Selecting Systems, of which the following is a full, elear,concise,

This invention relates to selecting systems particularly adapted for use in printing telegraph systems of the direct or keyboard limited to such use.

One of the objects otthis invention is to provide a system of the above type wherein the. same electromagnetic devices may be tivc current impulses.

Another object is to provide an improved system capable of very rapid operation by allouing the selecting and printing operations to take place simultaneously.

To the above ends a plurality of successively and coiiperativelyacting relays provide a succession of current impulses Whose character is determined by local current control means or are affected by a remotely produced succession 0t impulses, and cooperate with selecting mechanism whereby, the impulses formed or received effect the production of the desired results, such as the selecting and printing of characters. In combination. with the above apparatus, means are provided where by the printing of one character may proceed while the preliminary selections of the next succeeding character are taking place.

The above and other objects of this in'vention will befully set forth in the following description and claimsyand Will be more readily understood by reference to the acarrangement is shown diagrammatically, some of the mechanism being shown in perspective to more clearly illustrate'its method of operation. I

'lhesystem of this invention is particularly adapted for use with the \vellknown Baudot, code of five positive and negative impulses, and preferably requires but a single line conductor \vith'a ground return. When used as a transmitter, each key of a kqvboard arranged like that of an ordiiiary typewriter, upon'beiug depressed, among. other" things to be hereinafter described, op-

n; rename and .35 to ground. lieyla'uird magnet ('31. beclones energi el and, through the urgency of holding uuwlmnisnis (not ahouinh retains the contacts 1, 3. l. 50 and El in shifted position. and ia'u'itaeta so in cloned relation until the eirin'i 'iletion of the selecting opcraliens. The ehilting oil contact an from contact 5:? to contact, brings a pair oil polarized line and control relays I l and T1 and the main line .4 into conlnuuiication with the current impulse controlling;means. lt also arrange; the local malt-cling): apparaiuu under lhe inlhicnce oi till 5&2 polarized relays. 'llur lranaler of caramel Iii. lrom contart 33 to eontai-t .35. interpueea ini 'iuhse lcugrlluroinfgr relay 82: between the polarized relays To and Tl and the cut-oil relays ll. to 15. ll the armature: of polarizial relays I and T1 acted directly on coiuluctor 111,

the curl-ll relays it a; 15 might be energized and reuiorc the key coutae l to 5 from coluluclor T7 too soon to produrc an impulse of thrrequired duration. The time clement inirodluaal by theimpulaelengthenin;- relay H oun'romes this dillleulty.

The contacts controlled by the l? char- :nlri h y all having' been arranged and Eu -foal. a la'rrinlu-lore described, positive current. llou'a l'roui battery (3. contact 1. condurtor 7 back contact and armature 11? of rut-oil relay ll, conductors in and TT. contacts il and .70. and in parallel to line L and polarized relays TH and T1. Prefer ably. in order to give the best resulta, the branch including the relays Til-and T1. is niado approaiiuaatchc equal in resuatancc to that of line .l and the apparatus therein at the distant atatiou. This arrangenuait gives a good electrical balance to the two parallel. brain-bra traversed by tl'lfittlll'l'llll? impulses from battery (.5. It will. be assumed that polarixwl relay TU reaponda to negative currents only and that relay 71. responds to poei ire currents only. 'lhere'lore, current pasaing over the circuit just t'aced will cause relay T1 to attract, hoth its armatures F0 and S1. )Ullllllflljl't: 80 completes a circuit from ground, through conductor to, war l'fH'llH 51 and. 55, impulse lengthening relay Hill to grounded battery. Sal. causing relay 83 to idtr-acl. its armature. Arnuiture (ll courplot a circuit from. grounded battery 90. tumelllctnl 91. armattu'c and back iamtact ol mnnectiue relay '21, conductor Elil reelectin relay ll, conductors U4; and (33, and eontacts Maud 15 to ground. This circuit eases the energization of selecting relay 31, which thereupon. attracts its armatures 95 and ill The. attractimi of armature '36 complete z a circuit from. grounded battery 1UP]. selecting mag-net. ll. eonlrlurtor lllil. armature a l, conductor 10:! and hacl: contact and arniaturl': 103 of overlap relay lO-l togmund. The attraction ol armature 95 completes a holding circuit from grounded battery lllfi,

armaturea front contact and Winding of selecting: relay ill; eondluajors 9" and fill and contacts IS-l and 65 to grourul. This hold ing circuit. for the selecting relay l. insures the complete energization of the corre mud lug selecting n iaguet 4A. which asmsts in the selection of the desired character or operation and is: finally deiincrgized as hereinafter des ribed,

The energization of impulse lengthening relay 83 attraete its arinatiu'e 110 and closes a circuit from ground, through conductor 11,], armature 13.2 and back contact of con.- nei-tin r relay 2i, cul-oll relay 11 to battery .l 123 and grouni'h causing the ei'lergization of cubofl rel 3 ll. Relay 11 thereupon at.- t acts its armatures 11.7 and 116. Armature 1153, upon lmlng attracted, conrpletes a holdlug circuit for cut-oll' relay 11, through the connmetin r relay ill, by the .llolhm'ing path: grounded battery 113, cut-oil relay ll, connecting relay 21, front contact and arn'lature 1.1.). conductors 9-1 and 63, and contacts (3% and (15 to ground. The energization of connecting relay 21 is. however, prevented at this time due to a shunt to ground through its back contact and armature 112, conductor 1.11, and armature 110 ol. impulse lengthening: relay 83. The attraction of armature 11a of enroll relay 11 severe the circuit hereinhct'ore traced, from battery (1, through contact 1 to line L and polarized relays m lUNlYl, cutting off the first in:- pulse and allowing relay 71 to release its arinaturcs St) and 81. The retraction of armature 80 opens the circuit for relay 8 3, which thereupon releaaea its armature 110 opening the ground :ahunt for the previously traced. actuating and holding circuit through both cutoll relay ll and connecting relay $31, which now becomes active. calming connecting relay 21 to pull up all its arniatures. The retraction ol. armature S1 removes bat tcry from conductor 6)].

The pulling! up of all of the arniaturcs of connecting relay 111. performs three lunctiona: first. conductor 91 extended. through armature 532 and l'ront contact ol connecting relay :21 to coiuluctor 120, and from thence by back eontaelz and armature 121 of the accrual comumt-iug relay r32, eoialuctor 122, the second selecting relay 32, conductor. SH- and 6; and contacts ill and to ground; second. conductor 1.11 is extended through armature 112 and its 1orresponding front contact of ermueetin; relay ll, to conductor 25, and from thence by back contact and armature 126 of, second connectiiur relay 22,

through second rut-oll relay 1: to grounded battery lZT; and third, the pulling up of armature lfill joins the second key controlled contact 3 to line 1.. and polarized relays To and 71. through the back contact and armature lid of cut-oil relay ]2 and con- 'ductors 113i. and T7. The second impulse of i m ture 110' intense the combination is now acting on line L and polarized relays 70 and/71 and, since for letter F this impulse is assumed to be negative, relay 7() only will attract its ar mature. The armatureof relay 70, pulling ,up, completes "round conductor82 contacts 51 and 2: 7 .v 7

and impulse lengtheningrelay 83 to ground-' ed battery 84. Relay 83 pulls up its arinaand furnishes a ground. for the cirw cuit previously traced which includes the second cut-oft relay .12. Relay 12 attracts its armatures 131 and It will be noted 1 that, because the second key contact 2 was 15 not transferred to positiveto effect the char gization of polarized relay 71, the. circuit previously traced, which included thesec-v -and actuatingcircuit (from battery/.127 for 'cut-ofl' relay12-and connecting relay 22 by Way of conductorstl' land 6.3, and contacts As in the first in 6a and to ground. as stance, however, this circuit does notrbecome active'until relay 83 is deenergized, when the ground shunt by Way of armature 126, conduct0r125, front contact and armature 112 of relay '21, conductor 111 and '35 armature 110, is opened: When this shunt circuit is opened, duetohreaking of the circuit including key contact 2 and polarized relay 70, at the armature 131 of cutoff relay 12, connecting relay 22 is operated. In

40 pulling'up its three armatures,connecting relay extends conductors 120 and 125- on to the third cut-01f and connecting relays 13 and 23,;and joins key contact 3 to line L and polarized relays and 71 precisely in as the same manner as the first-connecting relay 21 extended cond third impulse has now started, and since it is assumed to, be; positive, polarized relay" 71 is again energized. The-attraction o-i' arma- 50 ture causes the energization of the third cut-oil relay l3 and the attraction of ELI": unature 81 causes the energizution of selooting relay 33 "and selecting magnet 43 in the same manner as that explained in con to nection with thefirst impulse. Cut-oil relay 13 terminates the third impulse and-connecting relay starts the fourth'impulsejand extends the circuit connections on to the fourth pair of relays 14 and 24. Thefourth an impulse is then terminated, the fifth impulse is initiated, and the control is extended to relays 15' and 25L Since we assumed that the fourth'and fifth. impulseswere respectively positive and negative, selecting relay e5 3t and selecting magnet etbecome operaan energizing circuit fromv magnet 42 remainv inert.

uctors 91and 111. The

- tire, whild selecting relay and are lockedv u magnet 45 remain inactive.

35 and selecting It is therefore.

readily apparent that selecting relays 31, 33

p by passing through contacts holding circuits 64: and 65, and

that the corresponding selecting magnets 41, 43 and 4-1- are locked up by holding circults passing through armature 103 of overlap relay 104;

Before proceeding further with the explanation of the operation of the circuit, some of the details of the mechanical selecting apparatus 'and printing in echanisin of the printer will be described in orderto insure a' clear understanding of the svsteui as an entirety. The characters are arranged in a double row on a type wheel 150 which 1s mounted one rotatable- 151 is caused, by any suita inally tend to rotate in th arrow, but except under presently described, is pre rotation by a holding p shaft 151; Shaft ble means, to nore direction of the conditions to be vented from such awl (not shown) underthe controlof a starter magnet 152.

Arranged concentrically with shaft 151 and placed oneabove the other are five selecting disks 24:1 to 245 inclusive, associated respectively with the selecting magnets all to notched periphery and eac moved through a sin spending selecting magnet the agency of an arm 250' h is adapted to be all angle by its corre- 'Each' of. the disks 241 to 245 has a all was through Y intercmmeeting the disk and its associated magnet armature '25l.

There is one notch in each 0 the disks correspending to each vertical on the type wheel 150 line of characters and an additional notch for each operation such as spacing, lincfeeding, etc, which it have the apparatus perform. line of notches corresponding is deemed desirable to Each vertical to a vertical line of characters on the type wheel is provided with a pivoted L-shaped sioned type selecting lever 255' sp ring-tenwlnch 18 adapted, under certain conditions to be hereother operations than type inafter explained, to engage with a stop arm wheel shaft 151. ches representing selections are also provided with spring-tensioued levers 257 adapted to control circuit connections, whereby the proper electromagnetic devices for performing the desired function are *ener-- gized as hereinafter described. Thus, whenvertical line i one of the type or o or more of the disks are,

moved by their corresponding magnets, a continuous and the of notches will be presented to peration selectinglevers spring thereof may, under conditions to be ipresently explained, force the inner end of the corrcsp arm 256'01' to proper circuit connect-ions. may therebybe arrested in ending lever upwardly into a. position toengage' the rotating cause the engagement of the The type wheel a'position to pre sent any desired character to the printing; platen, or the proper eleetrcniagnetic devices may he set in motion to space, feed the paper, shift the type Wheel, reset the paper carriage or accomplish any oi the other desirable op erations. The type selecting lovers 255 and the operation selecting levers i257 are nonniaily held out ol engagement with the scletting, disks ill to 453, and, after the cone pletion ot a cycle of operations, are restored to their normal position hy a, pair of release levers Qlll). Release levers "26!) have centrally projecting Glreulunslmpetl portions adapted to engage and depress the selecting levers under the tension olf springs Nil, \Yhcn release magnets cue are enerefixml, in a manner to he liereinal'tm' explained. however, the magnetic attraction overcomes the tension ot' sprin": J ll. and the centrally projecting: portions at the rehaise levers see are elevated, releasing the selectinglevers, one only of which, due to its coincidence with a line of notches in the selectin; disks, may more i sullicient amount to perform its function.

Returning: now to the serpience of operations, it will he readily understood that selecting dishs lit, i343 and ill-l have been i moved by their correspiuuling selecting magnets l1, l3 and l and are held in this position, while disks and 345 remain in norllltll position. The inovingof disks 241, and 2-H has caused the presentation of a complete vertical row of? notches before the proper type selecting lever and the mechanism is ready to cause the stopping of the type Wheel so that letter F may be presented to the paper and impressed thereon.

it will he noted that cut-elf relay la and connecting relay unlike the other cut'olf and connecting: relays, are provided each with only one armature. The creature of cut-off relay 1?) pulling up opens tlle circuit previously traced through the 'cyhoard holding n'iaguet 61 and all of the actuated key contacts oi? the current control means,

are returned to normal. The consequent shifting of contact 50 from contact; net to contact oilopeas the path for the negative impulse from battery (5, through contact. 5, and the fifth inipulse ceases. Thcrcupon' relays TO and 83 are deiinergized, opening the ground shunt for the circuit from battery 265, including both cut-off relay 15 and con necting relay 25, and connecting relay 25 is energized. The attraction of the armature of connecting relay 25 closes a circuit from ground thereat, conductor 266, back contact and armature 267 of: overlap relay 10%, and in parallel througlrhoth release magnets 262 to grounded battery 268. Release magnets thereupon cause the elevation of the con trally projecting portions of release levers 260, allowing the springs of the. selecting levers and 257 to start their respective r lovers in the performance of their function.

overlap relay IO-l, conductor racemes Only one selecting lever, however, viz. that representing the character 1 has a con tinuous row of notches presented tluu'eto and this lever only is allowed to raise its in \vardly projecting end in position to anger the arm 250 when the shalt is allmved to rotate. The movement of one at the release levers 260 likewise causes contact an to in: separated from contact U-l and to engage contact 275. This breaking and nmlcing; ol contacts performs two ,t'unctions. First, it; removes the ground connection from allot the holding circuits. lltd'tlllllt'lfil't traced, tor the operated selectiup relays i l to 35 and their correspoiulinfz selecting; magnets ll to 4-5, allowing, the relay arinatures to return to normal. The armatures oi. the selecting magnets also tend to return to normal hut the one selecting lever ivh'. .h has been forced into the line of notches prevents the return monument of the selecting: disks and consequently ot' the aruiatures 251 until released after the printing: or other operation has her-n performed, as hereinafter described. Second, it completes a circuit for the oven lap relay lUl from grounded hatteryfli'tl,

277 and contacts i575 and to ground. Overlap relay ItU-l: thereupon attracts its three armatures 103, 267 and E285.

The pulling up of armature 103 provides a new ground connection for the energizing circuits of selecting relays 31 to which heretofore included conductors till and 9-1. It also removes the ground'connection for the holding circuits of selecting magnets 41 to 4-5 so that, until the overlap relay 104 is dcencrgined, as hereinafter described, even the energiuation of the selecting relays can not cause the energization e'fthe correspond ing selecting magnets. It will, therefore, he rcadil y apparent theLthe ap iaratus having once chosen and operated a selecting le ver or 257 to hold the selection mechanically, and the overlap relay Lill -l having heeome energized, the selecting relays l .1 Lo 215 may he again actuated singly or in combi nation to select the next character or operation without interfering with the set up of the one preceding. When overlap relay 10- deenergized and its armature 103 returns to its back contact, all oi? the selecting mag nets -11 to 45 whose selecting relays 31 to 35 have beenencrgized by this secondset of impulses will he provided "with an operating and holding circuit, as hereinhefore described. This overlapping of the selecting and completing of the various operations al' lows the attainment of a very high speed. The separation of armature 267 of overlap ,relay lO-t from its back contact breaks the operating circuit. previously traced for the 3162186 magnets 26:2. These magnets are, however, not dcnergized at this tune for, upon thelr energization, they established a back contact holding circuit for themselves from groundedbattery 268, magnets 262, conductors 286, contact members 281, conductor 282, and

lay 283 to ground. The function performed by a circuit prepared by the engagement of ,contact will be attraction of a a circuit from closed contacts290 and 291 and grounded battery 292. Thiscauses the starter magnet 152, to withdraw the holding pawl heretofore referred to and shaft 151 begins to I lever 255, whereupon it ceases with The engagement of ,Printer magnet 296, platen (not shown) forces the paper againstlock relay 297 and consequently rotate in the direction of the engages the elevated end of the F the type wheel 150 in positionto print the letter F. stop arm 256 and the F selecting lever 255 closes a circuit from ground, through printer magnet 296, operating winding of space-lock relay 297, clearout relay 283 to grounded battery 298., Printer magnet 296, space-lock relay 297 and clear-out relay 283 now become active. by means of a suitable the type wheel. printing the character. Space-lockrelay 297, in pulling up its armatures, closes a divided circuit, bfrom grounded battery; 300, through spacer magnet 301 and its own holding winding 302. Spacer magnet 301 and, by means of suitable mechanisms (not shown) eifects the spacing of the paper to present a clean surface to'the printing platen. It also opens of the parallel circuit contact just traced at the spacer magnet 301 to become dcenergized in case the contact between stop arm 256 and the se lecting lever 255 has been broken, whichis usually the case, vbecause of the action of clear-put relay 283. It will be noted that the printing 'and paper spacing operations are initiated at the same time, but, due to the heavier and slower apparatus required to effect the spacing, the printing takes place first. The energization of clear-out relay 283 opens the previously traced holding circuit of the release magnets 262, whereupon their release levers 260, under the tension of springs 261, depress all of the type and operation selecting levers 255 and 257 includ ing the one engaging stop arm 256. This allows the displaced disks andv selecting magnet armatures to return to normal. Contacts 281 are returned to normal or separated condition, while contact 65 engages contact 64. and is separated from conand armature of a cie'ar-o-ut-ree clear-out relay 283,

of overlaprelay 104, conductor 287, starter magnet 152, conductor 289,

arrow. This. rotation continuesuntil the stop arm 256 selecting becomes, active the holding branch points 303, Which causes the space- 1 tact 275. The engagement between contacts 64 and 65 takes place prior to the separation [of contacts 65 and 275 in order that any iolding circuits which may have been formedby asubsequent selection of relays 31 to 35 may not be interrupted. The separation of contacts 65 and 275 deiine 'gizes overlaprelay 104, whosethree armatures returning to normal'again provides a ground connection, foiuany selecting magnet whose corresponding relayhasheen energized, rek establishes a partial magnets 262 which may be completed at the armature of connecting relay 25, and opens the energizing circuit of starter magnet 152. The letter F has now been printed, a clean surface of paper provided for the next character, and the printer apparatus returned to normal ready to set up the next selection provided by selecting relays 31 to 35. I i

In case, for any reason, on the printing of a character the stop Mm 256 on the type wheel shaft fails to engage the elevated selecting lever 255, the apparatus cannot be permanently tied up because of the failure of'the clear-out relay. ,Under thesecondicircuit. for the release tions the subsequent pulling up of connecting relay 25 completes a circuit from ground at its armature, conductor 266, armature 267 and front contact of overlaprelay 1041:, conductor310 and clear-out relay 283 to grounded battery 298. Clear-out relay 283 is thereupon energized and performs the functions it should have performed at the printing of the last character and only one character hasbeen lost, 'viz., that which was to have been printed when the stop arm 256 failed to engage selecting lever 255.

x If it is desired to move the paper carriage without printing a character, as in the case of a space between words, a combination of impulses minus, minus, plus, minus and minus will be prepared. Only key contact 4 will be transferred from minus to plus'and, as in the case of the F, impulse lengthening relay 83 and polarized relays 70 and 71 assisted by cut-off relays 11 to 15 and connecting relays 21 to 25 will cause the production of the necesproduction of letter sary five impulsesto be imparted to line L and will also effect the actuation of the required-selecting relays 31 to 35 and their (imthis case only the 44) Selecting disk 244, only, will be moved, which will cause the presentation of a con tinuous row of notches beforethe operation selecting lever ing of space contacts 312. The energization 257 adapted to effect the closof the last connecting relay 25 causes the operation of release levers 260 in the manner previously described,'whereupon the space contacts'312 are closed by the lever 257 and the'overlap relay 104 actuates its ar'rgatures.

lat

Armature lOil commute itu ground through the Front contact of overlap relay i l-l. eonluetorn U3 and 315. contacts ,512. opeating winding of fil'l u llti'lm'jli relay i397 and clean out relay 20 i to grouiuleil hatter-y 2H8. Hrmcwloelc relay 2%)? cfiectu the movement of the paper threlurh spacer nnuggnet i'll l, an prerioualy described, and the action of clearout relay starts: so soon and i; coniplet ed no rapidly that the previously tracedholding, circuit tor release magnets 2G2 and the operating circuit for the starter mat-net loll are hrolieu before the atarter magnet 152 can actuate its holding pawl, and conselpientl r the type wheel shaft d es not rotate.

in order to teed the paper from line to line, a eomhination of impulses produced which will client such a movement among lllSltH ill to Q -lfi that the selecting lever 25? which controls contact. 21H. will he :wtuated. lpon the operation of release magnets 2H2, contact 291 will he sepm'ated from contact 535a) and will engage. euntimt 320. This change of contacts cane-ea the. euergixation ol run magnet 321 which coiutroln nicehanisin (not shown) for feeding the pape' and an armature contact 322 for completing a circuit for the cl -ar-out relay It also opens the circuit for the starter magnet so that the tjg'pe nhait't will not rotate. This pria'autimi.to prevent the rotation oi. the type Wheel. in uilYiSulile in connection with the paper lei-ding. tor the mechanical pen Forming this Function conuiaratively heavy and nlugrn'ish and the. clear-out relay Stilt might not receive energizing tamtent soon enough to cauae the deiaiergiaation o'l rel ran ina nets 2G2 and starter magnet 152 before. the starter magnet had released the type wheel shaft.

its previously pointed out, the cha acters appear in a double row on the type wheel, the upper row heing normally in printing position. When it is desired to print some cluu-acter from the lower row. a coiohination of impulses in first produced which will cause the lifting of tilt. type wheel. Such a. eomhiuation of impulses controls selecting disks to cllhet the closing of contacts whereupon the. ahii'tiug magnet 326 encrglued. Magnet 3526. by in *ana of mechanism (not shiiuvn), litti; the type wheel and, by armature ta'nitact 32'", establishes a. holding circuit for itself from hattery ill-30, contact 327 shift magnet 326 to ground by way of imahi'l't contacta 331 and 332. The app ae. ratus is cleared out and returned to normal in the came manner as heretofore descrihed for the spacing: operation without allceting this holding circuit. The type Wheel is therefore held in shifted position and sub sequent character-n will he printed enthe lower row until a. comhiuatioi'i of impulses is formed to unahit't the wheel. pulses cause the transfer of contact 3352. from These imchill maglfuct 325 and rhiuiug a circuit tor the clear-out relay The paper rarriagc may he returned to the starting end oi? a line. In cauaiiuz the closing of contacts 3215. This energizeu the carriage return magnet Pith whereupon means (not shown) prorhuie the rerpiired result. Carriage return magnet 330 provides itself with a holding circuit from hatter 330 and armature contact 39ft", "which circuit is hroluen at contact -538 when the paper iarriage ranches the limit ol its return travel.

when the impulses for operating the. printer do not originate at the local keyhoaril. hut are received from the line L, the operation is in all respects similar to that hcreinhetore described except, of course, the key contacts 1 to 5, 50, 31 and 5C are undisturhed and the impulse lengthening rela v remains inactive. The incoming impulsra directly energize pi'ilarixed relay or 71, depending upon whether they are negative or positive, secure the serpiential operation ol cutoll' and connecting relays 11 to 15 and 21 to 25 respectively, and control the selecting relays 31 to 35 and selecting magnets; ll to ell i What claimed is? 1. it neleetii'ignystem comprising a current control means, a transiuissionf linc. and

a plurality oi relays acting invariably in the name sequence coiipe-ating with said means and associated with .Jaid line to produce a succession of impulses for said line or be operated by a screen. on of impulses over said line.

9.1x selecting system comprising a sclecting; mechanism, current control means, a tranerniissimi line. and a plurality of relays acting invariably in the same sequence ceo 'icrating with said selecting mechanism and said means to produce selections from impulnea over said line and to produce a succession of impulses for said line.

ll. selecting systen'i comprising local current control means, a tansmission line, a. plu 'ality of sequentially acting relays c0- opeating with said means and said line,

and an clectrornagnet and apparatus made operative by current supplied by said means or Sltltll line and. coiipc 'ating with said rclays to cause said relays to produce a succession of current impulsen for said line or operate thrmigh a succession of impulses over said line.

l. it. nelcctiug; cysteine comprising currentcontrol. means, a pluralit; of polarized relays controlledv by said means, and a series of relays operating sequentially under the control of said polar relays and coiiperating with said means to produce a selective sueccsn'ion of current impulses. i

it. selecting system comprising a plurality of type selecting levers from which w. to ill-l3. o ienin the hulilin circuit for one is to be selected, mea,ns for effecting such selection, a plurality of key contacts to control the action of said means, a'plurality of connecting relays successively causing said contacts to become active, and a plurality of cut-oft relays successively causing said ,contacts to become inactive, said cut-off relays controlling the action of said connecting relays.

- 6. A selecting system comprising current control means, a pair of control relays connected in parallel, and a plurality of relays fiowingin said line and 'the action of saidpolariied relay.

8. A selecting system comprising a selooting mechanism, a transmission line providing wsucoession of current impulses, a v

group of relays operating sequentially, and a second. group of relays cooperating with the relays of the first group and each depending upon the operation of all of the preceding the line impulses to effect the operation of said mechanism. I

9. A selecting system comprising a selectrelays of its group for causing ing mechanism, a group of relays operating sequentially, and a second group of relays all of which operatesequentially with the relays of the first groupto control each selective operation of said mechanism upon the-receipt of all combinations of series of current impulses.

10. In a selecting system the combination of-a plurality of members from which one s to means for causing the restoration of said selecting means, circuit connections for said clear-out means controlled by said member,

and. emergency circuit connections for said clear-out means independent of said member.

11. A selecting system comprising current control means, a plurality of sequentially acting relays cooperating with said means to produce a succession of current impulses,

and means cooperating with said'relays to lengthen. the duration of the impulses so produced.

12. AT selecting system comprising a se-- lecting mechanism, a transmission line providing a succession of current impulses, a plurality of relays acting successively and cooperating with said mechanism and .electromagnetic means cooperating With said relays to lengthen the duration of the line current impulses.

In Witness whereof, I hereunto subscribe e selected, selecting means for efiect- -1ng the selection of such member, clear-out my name this 17th day of March A. 1)., 1914-] I v AMOS F. DIXON. Witnesses: v

E. EDLER, NANON E. TUTHILL. 

